Last Updated: March 5, 2026 | Reviewed by The PCC Research Team
In the scorching heat of California’s inland valleys and high deserts, standard liquid insecticides break down quickly. Furthermore, tough pests like Bark Scorpions, Black Widows, and Turkestan Cockroaches often walk right over standard sprays without absorbing a lethal dose.
The 2026 Verdict: Cy-Kick or Onslaught FastCap?
Both utilize micro-encapsulation to survive the CA sun, but their kill speed and chemical “heat” vary significantly.
Choose Cy-Kick CS If:
You want a reliable, low-odor maintenance barrier. It is the steady “marathon runner” for ants, crickets, and general spiders where immediate knockdown isn’t the priority.
Choose Onslaught FastCap If:
You are battling Scorpions or aggressive spiders. This is a “stacked” formula designed to kill on contact while leaving a durable residual barrier for the desert heat.
Quick Navigation:
1. Science: The Micro-Cap Advantage
| Feature | Cy-Kick CS (Cyfluthrin) | Onslaught FastCap (Esfenvalerate) |
|---|---|---|
| Formulation | Pure Micro-capsule | Micro-capsule + Synergist + Knockdown |
| Primary Strength | 90-Day Durability | Immediate Contact Kill + Residual |
| Kill Speed | Slow to Moderate | Fast (Prallethrin-enhanced) |
| Best For | General maintenance, Ants | Scorpions, Black Widows, Roaches |
2. Cy-Kick CS: The Marathon Runner
Cy-Kick CS is the reliable industry standard. It encases Cyfluthrin in a durable polymer shell. It is not designed for instant kills; a scorpion might cross the barrier and die a day later. The goal is long-term population control. It is broadly labeled for indoor/outdoor use and is known for having very low odor and irritation potential.
3. Onslaught FastCap: The Sprinter
Onslaught FastCap solves the “slow kill” problem of micro-caps. It contains Prallethrin (fast kill) and PBO (a synergist that supercharges the poison) outside the capsules for immediate action. The Esfenvalerate inside the capsules handles the long-term work. This is widely considered the best perimeter spray for scorpions in California deserts.
Critical Note: Onslaught FastCap is a “hotter” formulation. While highly effective, use caution indoors on sensitive surfaces and always keep pets away until it is 100% dry, as it can be more irritating than Cy-Kick.
4. UV Resistance in California
In regions like Riverside or Palmdale, standard sprays evaporate within days. The polymer spheres in both Cy-Kick and Onslaught sit on top of porous surfaces like stucco and concrete rather than soaking in. This protects the active ingredients from degrading under intense California UV sunlight, providing up to 90 days of defense.
5. Frequently Asked Questions
Q: What is the main difference between Cy-Kick CS and Onslaught FastCap?
A: Cy-Kick is a pure micro-capsule for long-term maintenance. Onslaught FastCap adds a knockdown agent and a synergist (PBO) to kill bugs faster on contact while still providing a long-term barrier.
Q: Which is better for scorpions in California?
A: Onslaught FastCap is superior for scorpions. The “FastCap” technology ensures the scorpion picks up the fast-acting killing agents immediately, preventing it from wandering too far before it dies.
Q: How long do these barriers last?
A: In ideal conditions, both can last 90 days. In the peak of the California summer with daily irrigation and 100F+ temperatures, we recommend re-applying every 60 days for maximum protection.
Infestation Too Tough for DIY?
If you have scorpions in your shoes or Black Widows in your garage, sometimes professional equipment is needed to reach the deep harborage points.
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